Authorities say Elliot Rodger stabbed three male students in his apartment before he began shooting at sorority girls and bystanders. He left behind a string of YouTube videos and a manifesto detailing his disdain for the women who spurned him and the men they chose instead.

“These mass shootings are too often followed by stories about the perpetrator’s history of severe mental illness,” Kelly wrote on behalf of Americans for Responsible Solutions, the PAC he and Giffords co-founded. “Thankfully, taking action on mental health and protecting women from gun violence and intimidation are issues Democrats and Republicans can agree on — despite the filibuster of expanded background checks last year.”

The Senate rejected a bill in April 2013 that would have expanded background checks on gun purchasers. Action by Congress on major gun control legislation is unlikely, especially in an election year.

Sen. Dianne Feinstein, D-Calif., a leading gun control advocate, also denounced the ease in which guns are obtained.

“Americans need to rise up and say enough is enough,” Feinstein said in a statement issued this weekend. “Until that happens, we will continue to see these devastating attacks. Shame on us for allowing this to continue.”